Having discussed how the law of torts protects a person’s physical integrity and freedom of movement in the previous chapter, we will now consider how the law protects a person’s interests in property against certain types of interference, including trespass to land and trespass to personal property

In this chapter, we will explore the definitions and features of these trespass actions.

This chapter deals with defences to the trespass actions discussed in Chapters 6 and 7. As a general rule, the defendant bears the burden of proving the facts necessary to constitute a defence. Where the defence is established, the defendant will be relieved of liability.

It should be noted that some statutory defences, which are similar to common law defences, are provided by the civil liability legislation and/or Criminal Code in most of the Australian states and territories. Therefore, when considering such defences, the relevant legislation in a particular jurisdiction must be consulted. This chapter will discuss some of the most important defences available for trespass to the person, trespass to land and trespass to personal property.

The defences fall within three roughly divided categories:

1. (1) Self-help based defences

2. (2) Justification-based defences

3. (3) Fault-based defences

   We also consider a number of factors that are not defences to trespass at the end of this chapter.

‘Trespass’ is a generic term encompassing a set of wrongs involving direct, and usually intentional, interference with either the person or property affected. There are three different forms of trespass actions: trespass to the person, trespass to land and trespass to goods (chattels).

These trespass actions create a number of fundamental common law rights protecting a plaintiff’s personal dignity, desire for autonomy, interests in the physical integrity of people’s body and the exclusive possession of land and goods. While the common aim of these forms of action is to protect the fundamental common law rights of a person, the ingredients of each tort are quite disparate.

This chapter first considers the historical origins of trespass, before discussing the trespass action. It then deals with the tort of ‘trespass to the person’ as well as three nominate torts under this form of action, before discussing remedies available for trespass to the person.

This chapter considers three different torts: battery (unlawful physical touching); assault (an apprehension or threat of unlawful touching); and false imprisonment (unlawful confinement or constraint). While their common aim is to protect the integrity of C’s person, the ingredients of each tort are quite disparate.

As a preliminary matter of terminology: trespass to the person is a form of action, but assault, battery, and false imprisonment are causes of action.

This book chapter advances a hypothesis that judges tend to avoid ex post inefficiency (that is, inefficiency falling to litigants), but judges are less inclined to avoid ex ante inefficiency (that is, inefficiency incurred by future parties). Drawing on three empirical studies which the author has conducted on property cases rendered by courts in Taiwan, this chapter presents preliminary evidence to test this hypothesis. The three studies are consistent with the hypothesis, as judges avoid ex post inefficiency in two studies (co-ownership partition and building encroachment) but fail to avoid ex ante inefficiency in one study (trespass to land).